Patents by Inventor Toshiyuki Ugai

Toshiyuki Ugai has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 6835521
    Abstract: To provide a process for producing toner particles in a good efficiency which have less residue of monomers and less other organic volatile components, the process has a polymerization step of polymerizing a polymerizable monomer composition containing at least a polymerizable monomer, in a vessel holding therein an aqueous medium, wherein a high-temperature saturated steam with a temperature higher than 100° C. is introduced into the aqueous medium held in the vessel, at the latter half of polymerization or after the polymerization has been completed, to remove at least organic volatile components from toner particles having at least a binder resin and a colorant.
    Type: Grant
    Filed: January 24, 2003
    Date of Patent: December 28, 2004
    Assignee: Canon Kabushiki Kaisha
    Inventors: Yoshinori Tsuji, Toshiyuki Ugai, Akira Hashimoto, Hidekazu Fumita
  • Publication number: 20040259018
    Abstract: To provide a process for producing toner particles in a good efficiency which have less residue of monomers and less other organic volatile components, the process has a polymerization step of polymerizing a polymetizable monomer composition containing at least a polymerizable monomer, in a vessel holding therein an aqueous medium, wherein a high-temperature saturated steam with a temperature higher than 100° C. is introduced into the aqueous medium held in the vessel, at the latter half of polymerization or after the polymerization has been completed, to remove at least organic volatile components from toner particles having at least a binder resin and a colorant.
    Type: Application
    Filed: July 13, 2004
    Publication date: December 23, 2004
    Applicant: CANON KABUSHIKI KAISHA
    Inventors: Yoshinori Tsuji, Toshiyuki Ugai, Akira Hashimoto, Hidekazu Fumita
  • Publication number: 20030224276
    Abstract: To provide a process for producing toner particles in a good efficiency which have less residue of monomers and less other organic volatile components, the process has a polymerization step of polymerizing a polymerizable monomer composition containing at least a polymerizable monomer, in a vessel holding therein an aqueous medium, wherein a high-temperature saturated steam with a temperature higher than 100° C. is introduced into the aqueous medium held in the vessel, at the latter half of polymerization or after the polymerization has been completed, to remove at least organic volatile components from toner particles having at least a binder resin and a colorant.
    Type: Application
    Filed: January 24, 2003
    Publication date: December 4, 2003
    Inventors: Yoshinori Tsuji, Toshiyuki Ugai, Akira Hashimoto, Hidekazu Fumita
  • Patent number: 6346356
    Abstract: A toner is comprised of toner particles containing at least a binder resin, a colorant, a wax component and an oxycarboxylic acid. The toner satisfies the following conditions: 1.05≦A/B≦3.00, and 0.15≦B≦3.50 wherein A (mg) is a weight of oxycarboxylic acid extracted with methanol from 1 g of the toner, and B (mg) is a weight of oxycarboxylic acid extracted with an aqueous 0.1 mol/liter sodium hydroxide solution from 1 g of the toner.
    Type: Grant
    Filed: May 17, 2000
    Date of Patent: February 12, 2002
    Assignee: Canon Kabushiki Kaisha
    Inventors: Manabu Ohno, Toshiyuki Ugai, Ryoichi Fujita, Shinya Yachi, Yasushi Katsuta, Kenichi Nakayama
  • Patent number: 6285848
    Abstract: An electrophotographic apparatus includes an electrophotographic photosensitive member, and (i) a charger, (ii) an imagewise exposure device, (iii) a developing device and (iv) a transfer device, disposed in this order opposite to the photosensitive member. The charger includes a charging member including magnetic particles disposed in contact with the photosensitive member so as to charge the photosensitive member based on a voltage received thereby. The magnetic particles are surface-coated with a coupling agent having a linear alkyl group having a least 6 carbon atoms. The developing device also functions to recover residual toner remaining on the photosensitive member processing by the transfer device and the charger. Because of the coating with such a specific coupling agent, the charging magnetic particles can exhibit good triboelectric changeability for the transfer residual toner for a long period.
    Type: Grant
    Filed: June 8, 1998
    Date of Patent: September 4, 2001
    Assignee: Canon Kabushiki Kaisha
    Inventors: Shuichi Aita, Kenji Okado, Toshiyuki Ugai, Ryoichi Fujita, Fumihiro Arahira, Kiyoshi Mizoe, Yoshifumi Hano
  • Patent number: 6054244
    Abstract: A process for producing a toner comprises the steps of: adjusting to 4.0 to 6.0 the pH of an aqueous medium containing a calcium phosphates obtained by mixing an aqueous phosphate solution with an aqueous calcium salt solution; dispersing in the aqueous medium a polymerizable monomer composition having at least a polymerizable monomer, a colorant, a polar polymer or polar copolymer having a carboxyl group, and a polymerization initiator to form particles of the polymerizable monomer composition; in the aqueous medium, polymerizing the polymerizable monomer contained in the particles to form toner particles; and adjusting the pH of the aqueous medium to 1.0 to 3.0 to dissolve the calcium phosphate, followed by separating the toner particles from the aqueous medium. The circularity of the toner obtained is not less than 0.970 and less than 1.000 as measured with a flow-type particle image analyzer (FIPA).
    Type: Grant
    Filed: December 23, 1998
    Date of Patent: April 25, 2000
    Assignee: Canon Kabushiki Kaisha
    Inventors: Kazunori Kato, Toshiyuki Ugai, Satoshi Yasuda
  • Patent number: 6030737
    Abstract: A non-magnetic toner for developing an electrostatic image has non-magnetic toner particles produced by polymerizing in an aqueous medium a polymerizable monomer composition containing at least a polymerizable monomer, a carbon black and an azo type iron compound. The carbon black has a DPB oil absorption of from 110 ml/100 g to 200 ml/100 g, a specific surface area of 100 m.sup.2 /g or below as measured by nitrogen adsorption, a volatile component of 2% or less and an average primary particle diameter of from 20 m.mu. to 60 m.mu., and the azo type iron compound is a compound represented by the following Formula (1).
    Type: Grant
    Filed: November 12, 1997
    Date of Patent: February 29, 2000
    Assignee: Canon Kabushiki Kaisha
    Inventors: Toshiyuki Ugai, Kenji Okado
  • Patent number: 6015647
    Abstract: A toner for developing an electrostatic image is composed of toner particles containing at least a binder resin, a colorant and a wax composition. The wax composition comprises an ester wax (1) having a long-chain alkyl group, and a wax (2). The wax (2) shows a maximum heat-absorption peak in a range of 40-130.degree. C. on temperature increase on a DSC (differential scanning calorimeter) curve, and gives a .sup.13 C-NMR (nuclear magnetic resonance) spectrum showing a total peak area S in a range of 0-50 ppm, a total peak area S1 in a range of 36-42 ppm, and a total peak area S2 in a range of 10-17 ppm, satisfying: 1.0.ltoreq.(S1/S).times.100.ltoreq.10, 1.5.ltoreq.(S2/S).times.100.ltoreq.15, and S.sub.1 <S.sub.2. The toner particles contain A wt. parts of the ester wax (1), B wt. parts of the wax (2) and C wt. parts of the colorant, respectively per 100 wt. parts of the binder resin, satisfying: 3.ltoreq.A.ltoreq.30, 0.2.ltoreq.B.ltoreq.10, 4.ltoreq.A+B.ltoreq.40, 0.02.ltoreq.B/A.ltoreq.0.5, and 0.02.
    Type: Grant
    Filed: April 13, 1999
    Date of Patent: January 18, 2000
    Assignee: Canon Kabushiki Kaisha
    Inventors: Toshiyuki Ugai, Manabu Ohno
  • Patent number: 5994019
    Abstract: An image forming method is disclosed in which a contact charging means is brought into contact with a latent image bearing member to electrostatically charge the latent image bearing member on which electrostatic latent images are formed and developed with a one component type or two component type developer to form toner images, using a developing assembly provided with a developing container and a developer carrying member. The one component developer is comprised of toner particles. The two component type developer is comprised of toner particles and a magnetic carrier. The toner particles of the one component type and two component type developers contains fine particles as an external additive.The latent image bearing member has a surface layer having a volume resistivity A of from 10.sup.8 to 10.sup.15 .OMEGA..multidot.
    Type: Grant
    Filed: November 26, 1997
    Date of Patent: November 30, 1999
    Assignee: Canon Kabushiki Kaisha
    Inventors: Kenji Okado, Toshiyuki Ugai, Ryoichi Fujita, Kazumi Yoshizaki
  • Patent number: 5989770
    Abstract: A process for producing a toner for developing an electrostatic latent image. The process has the steps of dispersing in an aqueous medium having a pH of from 4.5 to 8.5 a polymerizable monomer composition containing at least a polymerizable vinyl monomer, a colorant, an organic metal compound, an aromatic carboxylic acid, a polyester resin having an acid value of from 5 mg.multidot.KOH/g to 50 mg.multidot.KOH/g, and a polymerization initiator, to form particles of the polymerizable monomer composition in the aqueous medium, and polymerizing the polymerizable vinyl monomer in the particles of the polymerizable monomer composition.
    Type: Grant
    Filed: January 28, 1999
    Date of Patent: November 23, 1999
    Assignee: Canon Kabushiki Kaisha
    Inventors: Toshiyuki Ugai, Satoshi Yasuda, Kazunori Kato
  • Patent number: 5885742
    Abstract: A carrier for electrophotography has carrier particles. Each carrier particle has a carrier core and a silicone resin coat layer that covers the carrier core. The carrier particle has silicon atoms and carrier atoms on its surface in the ratio that satisfies the condition of Si/C=0.1 to 2.0 as the number of atoms present on the carrier particle surface as measured by X-ray photoelectron spectroscopy, and from 0.1% by number to 5% by number of metal atoms are present on the carrier particle surface. Additionally, there is a two-component developer for developing electrostatic images which consists of a toner and the carrier. An image forming method in which the two-component developer having the toner and the carrier is transported to a developing zone which is defined by a latent image carried on a latent image bearing member to develop the latent image. A voltage is applied to the developer to direct the toner from the latent image bearing member to a member carrying the developer.
    Type: Grant
    Filed: October 3, 1997
    Date of Patent: March 23, 1999
    Assignee: Canon Kabushiki Kaisha
    Inventors: Kenji Okado, Toshiyuki Ugai, Ryoichi Fujita, Tsuyoshi Takiguchi
  • Patent number: 5856055
    Abstract: An electrophotographic black toner containing carbon black in a good dispersion state as well as a combined charge control agent system including a specific azo iron metal compound of formula (1) shown below and an oxycarboxylic acid metal compound is produced through polymerization in an aqueous system. The combined charge control agent system shows an effects of synergistically improving the chargeability of spherical polymerized toner particles. The azo iron metal compound improves the dispersion of the carbon black in the toner particles. ##STR1## wherein the denotations of R.sub.1 -R.sub.6, n, n' and A.sup..sym. are omitted.
    Type: Grant
    Filed: March 31, 1998
    Date of Patent: January 5, 1999
    Assignee: Canon Kabushiki Kaisha
    Inventors: Toshiyuki Ugai, Kazumi Yoshizaki
  • Patent number: 5774771
    Abstract: An image forming method has a developing step of developing an electrostatic latent image by the use of a developer to form a toner image on an electrostatic latent image bearing member, a primary transfer step of transferring the toner image onto an intermediate transfer member to which a voltage is applied, and a secondary transfer step of transferring onto a transfer medium the toner image held on the intermediate transfer member, while a transfer means to which a voltage is applied is pressed against the transfer medium. The developer has a toner. The toner is a black toner having at least i) black toner particles formed of a binder resin with a colorant dispersed therein and ii) an inorganic fine powder. The black toner has the value of shape factor SF-1 of 110<SF-1.ltoreq.180, the value of shape factor SF-2 of 110<SF-2.ltoreq.140, and the value of ratio B/A of 1.
    Type: Grant
    Filed: February 9, 1996
    Date of Patent: June 30, 1998
    Assignee: Canon Kabushiki Kaisha
    Inventors: Tsutomu Kukimoto, Motoo Urawa, Kenji Okado, Toshiyuki Ugai, Keita Nozawa, Satoshi Yoshida, Yuki Karaki
  • Patent number: 5733702
    Abstract: An image forming method is conducted by forming a toner image on a latent image bearing member containing an organic photoconductive material. The latent image bearing member includes a photosensitive layer containing an organic photoconductive material and a protective layer which contains fluorine-containing resin particles in an amount from 5% by weight to 40% by weight. The toner contains toner particles and external additives. The external additives include titanium oxide particles having a weight average particle diameter from 0.01 .mu.m to 0.2 .mu.m having been subjected to hydrophobic treatment, organic resin particles having a weight average particle diameter from 0.02 .mu.m to 0.5 .mu.m, and inorganic compound particles having a weight average particle diameter from 0.5 .mu.m to 2.5 m.The inorganic compound particles may be specific titanates, oxides or carbonate.
    Type: Grant
    Filed: April 5, 1995
    Date of Patent: March 31, 1998
    Assignee: Canon Kabushiki Kaisha
    Inventors: Kenji Okado, Toshiyuki Ugai, Ryoichi Fujita, Tsuyoshi Takiguchi, Yasuhiro Ichikawa
  • Patent number: 5698354
    Abstract: An image-forming method is comprised of delivering a transfer-receiving medium to a first image-forming unit, forming a first toner image by a first image-forming means of the first image-forming unit, transferring the first toner image onto the transfer-receiving medium at a first transfer section of the first image-forming unit with a first transfer bias applied, and delivering the transfer-receiving medium to a second image-forming unit. Forming a second toner image by a second image-forming means of the second image-forming unit, transferring the second toner image onto the transfer-receiving medium carrying the first toner image at a second transfer section of the second image-forming unit with a second transfer bias applied, fixing the first toner image and the second toner image transferred on the transfer-receiving medium by a fixing means.
    Type: Grant
    Filed: February 9, 1996
    Date of Patent: December 16, 1997
    Assignee: Canon Kabushiki Kaisha
    Inventors: Toshiyuki Ugai, Tatsuya Nakamura
  • Patent number: 5670288
    Abstract: A carrier for electrophotography has carrier particles. The carrier has a 50% average particle diameter (D.sub.50) of from 15 .mu.m to 45 .mu.m and contains from 1% to 20% of carrier particles with a size smaller than 22 .mu.m, not more than 3% of carrier particles with a size smaller than 16 .mu.m, from 2% to 15% of carrier particles with a size of 62 .mu.m or larger, and not more than 2% of carrier particles with a size of 88 .mu.m or larger. The carrier has a specific surface area S.sub.1 as measured by an air-permeability method and a specific surface area S.sub.2 as calculated by the following expression:S.sub.2 =(6/.rho..multidot.D.sub.50).times.10.sup.4wherein .rho. is a specific gravity of carrier; satisfying the following condition:1.2 .ltoreq.S.sub.1 /S.sub.2 .ltoreq.2.0.
    Type: Grant
    Filed: February 12, 1996
    Date of Patent: September 23, 1997
    Assignee: Canon Kabushiki Kaisha
    Inventors: Kenji Okado, Toshiyuki Ugai, Ryoichi Fujita, Makoto Kanbayashi, Tsuyoshi Takiguchi, Yasuhiro Ichikawa, Wakashi Iida
  • Patent number: 5637432
    Abstract: The present invention provides a toner for developing an electrostatic image, comprising toner particles and external additives, wherein;said external additives comprise (A) titanium oxide particles having a weight average particle diameter of from 0.01 .mu.m to 0.2 .mu.m, having been subjected to hydrophobic treatment, (B) organic resin particles having a weight average particle diameter of from 0.02 .mu.m to 0.5 .mu.m and (C) an inorganic compound having a weight average particle diameter of from 0.5 .mu.m to 2.5 .mu.m; said external additives being added in an amount satisfying the relationship:(A):(B)=2:1 to 10:1(A):(C)=1:1 to 5:1; andsaid toner contains toner particles having a particle diameter of from 2 .mu.m to 5 .mu.m in an amount of from 15% by number to 40% by number.
    Type: Grant
    Filed: February 28, 1995
    Date of Patent: June 10, 1997
    Assignee: Canon Kabushiki Kaisha
    Inventors: Kenji Okado, Toshiyuki Ugai, Ryoichi Fujita, Tsuyoshi Takiguchi, Yasuhiro Ichikawa
  • Patent number: 5512402
    Abstract: A carrier for electrophotography has carrier particles. The carrier has a 50% average particle diameter (D.sub.50) of from 15 .mu.m to 45 .mu.m and contains from 1% to 20% of carrier particles with a size smaller than 22 .mu.m, not more than 3% of carrier particles with a size smaller than 16 .mu.m, from 2% to 15% of carrier particles with a size of 62 .mu.m or larger, and not more than 2% of carrier particles with a size of 88 .mu.m or larger. The carrier has a specific surface area S.sub.1 as measured by an air-permeability method and a specific surface area S.sub.2 as calculated by the following expression:S.sub.2 =(6/.rho..D.sub.50).times.10.sup.4wherein .rho. is a specific gravity of carrier; satisfying the following condition:1.2.ltoreq.S.sub.1 /S.sub.2 .ltoreq.2.0.
    Type: Grant
    Filed: May 19, 1994
    Date of Patent: April 30, 1996
    Assignee: Canon Kabushiki Kaisha
    Inventors: Kenji Okado, Toshiyuki Ugai, Ryoichi Fujita, Makoto Kanbayashi, Tsuyoshi Takiguchi, Yasuhiro Ichikawa, Wakashi Iida
  • Patent number: 5102761
    Abstract: A color toner for developing an electrostatic latent image, which includes a binder resin, a xanthene-type dye and a compound containing a phenolic --OH (hydroxyl) group.
    Type: Grant
    Filed: May 1, 1990
    Date of Patent: April 7, 1992
    Assignee: Canon Kabushiki Kaisha
    Inventors: Ichiro Ohsaki, Takaaki Kohtaki, Yuko Sato, Hiroyuki Kobayashi, Toshiyuki Ugai